ps1 is not where started you need to find a super nintendo those games will stand up to time itself ,getting back on topic the most memorable game for me would be ...

Galerians it was unique game for the time that came out, starts off with young boy in hospital being injected with drugs and gives him powers, in order to maintain them you would have to find and coninue to use them, ....
i could talk about this game all day but since sort of rare i doubt people would be able to make any connections it was made into a short film if your curious but it doesn't do it justice

i loved all ps1 game ._. but chrono cross and ff tactics as well as mgs v.v have that special place in my heart alssssooooooo if you havnt played them ;D thier all three on psn so for the win people O:< oh and almost forgot two more parasite eve seris omg and cant rem name well but somthing to do with magical body building protien drink it was a japanese exclusive with body builders flying around shooting lazers......and well i guess the name explains it XDD also on psn i believe

Hnggg. Tough one.
I am still in love with my PS1.
Street Fighter EX Plus A, definitely.
I've grown into a pro after all these years :3
Oh and Spyro I, II and III, and CTR and Crash Bandicoot.
Tomb Raider, Alien and Tekken. Hmm and maaany more.